Yes. Filtering for relevant information is part of good case analysis. You do not need to use every number simply because it appears in the exhibit.

Assessment questions can include more information than you need. The skill is to connect the question to the right variables quickly instead of processing the entire chart with equal weight.

If the question asks about profit change in one segment, total company headcount or another segment's volume may be visible but irrelevant to the calculation.

Start by restating exactly what the question asks, identify the variables required to answer it, and then scan the exhibit for those inputs before looking at secondary details. If useful, this guide on case interview preparation gives more detail.

Yes, filtering is part of it. Not every number is there because you need it.

I used to waste time trying to use everything on the chart.

Question first, then data.